Easy clean lint filter



May 23, 1967 H. BERKE EASY CLEAN LINT FILTER Filed Jan. 27, 1965 INVENTOR.

HOWARD L. BERKE ms ATTORNEY 3,320,678 EASY CLEAN LINT FILTER Howard L. Berke, Louisville, Ky., assignor to General Electric Company, a corporation of New York Filed Jan. 27, 1965, Ser. No. 428,412 3 Claims. (CI. 34-82) This invention relates to filters, and more particularly to lint filters for use in automatic fabric dryers.

Automatic fabric dryers normally include a filter to remove lint from the vitiated air before it is exhausted from the machine. To perform effectively the filter must be so constructed and positioned as to intercept substantially all the air being exhausted. During machine operation a body of lint builds up on the surface of the filter. If it is not removed, the lint will interfere with the proper flow of vitiated air, thus, hampering the proper performance of the dryer. Prior art filters are difficult to clean, particularly when the lint coating is light; therefore the average user tends to allow too much lint to accumulate before cleaning the filter.

An object of my invention is to provide an improved lint filter for use in automatic fa'bric dryers.

Another object of my invention is to provide such an improved filter which may be quickly and easily cleaned.

In carrying out my invention, in one form thereof, I provide a lint filter for mounting in the duct which directs vitiated air from the dryer. The filter includes a perforated filtering member which extends substantially across the duct and is formed with a plurality of small, closely spaced openings which strain lint from the vitiated air. In order to facilitate cleaning the filter I provide a narrow, elongated, imperforate rib which is bounded on at least two sides by the perforated filtering member. The rib provides an area in which lint particles are not entangled in openings in the filtering member and presents a surface against which the user may apply a sliding force in re moving the lint.

The subject matter which I regard as my invention is particularly pointed out and distinctly claimed in the concluding portion of this specification. My invention, both as to organization and method of operation together with further objects and advantages thereof, may best 'be understood by reference to the following description taken in conjunction with the accompanying drawing.

In the drawing, FIGURE 1 is a fragmentary side elevational view of a clothes dryer incorporating one embodiment of my improved lint filter, the view being partly broken away and partly sectionalized to illustrated de tails; and

FIGURE 2 is a perspective view of the lint filter shown in FIGURE 1, the view being partly broken away for purposes of illustration.

Referring now to FIGURE 1, the machine illustrated is a domestic clothes dryer generally indicated by the numeral 1. Dryer 1 is provided, in the usual way, with a cabinet 2 having a front door 3 to provide access to the interior of the cabinet for loading or unloading clothes. Provided on the top wall 4 of the cabinet is a control panel 5 which may, in the conventional way, include a suitable manual control 6 connected to a sequence control assembly 7 mounted in panel 5. By a manual presetting of control 6 the machine may be caused to start, and automatically proceed through a cycle of operations.

Within cabinet 2, there is provided a clothes tumbling container or drum 8 mounted for rotation on a substantially horizontal axis. Drum 8 is substantially cylindrical in shape having a first outer cylindrical wall portion 9, second and third outer cylindrical wall portions 1%) and 11 located respectively adjacent the front and back of the drum, a front wall 12 and a back wall 13. Outer States Patent 3,329,678 Patented May 23, 1967 add 9 there may be provided a plurality of clothes tumbling ribs 14 so that the clothes are lifted up when the drum rotates, and then are tumbled back down to the bottom of the drum. The front of drum 8 may be rotatably supported within outer casing 2 by suitable idler Wheels, one of which is shown at 15. These wheeis are rotatably secured to the top of a member 16 which extends up from base 17 of the machine. Wheels 15 are disposed beneath the drum in contact with portion 10 thereof so as to support portion 11) on each side to provide a stable support.

The rear end of drum 3 receives its support by means of a stub shaft 18 extending from the center of wall 13. Shaft 18 is secured within a bearing 19 formed in a baffle 20 which, in turn, is rigidly secured to the back Wall 21 of cabinet 2 by any suitable means such as, for instance, welding at a number of points 22. With the arrangement shown, the basket may rotate on a horizontal axis with rollers 15 providing the front support, and stub shaft 18 Within bearing 19 providing the rear support. In order to provide for the flow of a stream of drying air through the clothes drum, the drum is provided with a central opening 23 in its front Wall 12 and with an opening in the form of a plurality of perforations 24 in its rear wall 13, the perforations in the present case being formed to extend around the rear wall in an annulus.

As has been stated, baffie member 20 is rigidly secured to rear wall 21 of cabinet 2. Bafiie member 20 also serves to support heating means such as electrical heating elements 25 appropriately insulated from the baffle wall portions 9, 10 and 11 are imperforate over their member. Elements 25 may be annular in shape so as to be generally coextensive with perforations 24 and drum 3. A bafiie member 26 is rigidly secured to the back wall 13 of the drum outside the ring of perforations 24 and within the stationary bafiie 20, so that an annular air inlet 27 is, in effect, formed by the bafiies 20 and 26. In this manner, an inlet passage is formed for air to enter annular inlet opening 27 between the bafiles, pass over the heater 25, and then pass through openings 28 formed in baffle 26 to the interior of drum 8. The front opening 23 of the drum is substantially closed by means of a stationary bulkhead generally indicated by the numeral 29. Bulkhead 29 is made up of a number of adjacent members including the inner surface 30 of access door 3, a stationary frame 31 for the door formed as a flange of front wall 32 of the cabinet, the inner surface member 33 of an exhaust duct which is formed by the cooperation of member 33 with the front wall 32 of the cabinet, and an annular flange 34 mounted on frame 31 and on the duct wall. It will be noted that a suitable clearance is provided between the inner edge of drum opening 23 and the edge of bulkhead 29 so that there is no rubbing between the drum and the bulkhead during rotation of the drum. In order to prevent any substantial air leakage through opening 23 between the interior and the exterior of the drum, a suitable ring seal 35, preferably formed of felt-like material, is secured to flange 34 in sealing relationship with the exterior surface of drum wall 12.

Front opening 23, in addition to serving as part of the air flow path through the drum, also serves as a means whereby clothes may be loaded into and unloaded from the drum. Door 3, whose inner surface forms part of the bulkhead closing the opening, is mounted on cabinet 2 so that when the door is opened clothes may be inserted into or removed from the drum through the door frame 31. It will be noted that the door includes an outer fiat imperforate section 36 and an inwardly extending hollow section 37 mounted on the flat outer section. Hollow section 37 extends into the door frame a) 31 when the door is closed, and the door surface 30 which comprises part of the combination bulkhead 29 is actually the inner wall of the hollow section.

The air outlet opening from the drum is provided by perforated opening 38 formed in the inner wall 30 of hollow door section 37. The bottom wall section of door 3 and the adjacent wall of door frame 31 are provided with aligned openings 39 and 41), opening 40 providing the entrance to the duct 41 formed by the cooperation of member 33 with front wall 32. As shown, my new and improved lint trap 42 is positioned in the exhaust duct 41 at opening 40. The trap includes a rigid frame 43 which rests on the upper end of member 33 and front wall 32. Frame 43 is attached to and supports a filtering member 44 which extends substantially across the duct and thereby intercepts substantially all of the vitiated air that is exhausted from drum 8.

Duct 41 leadsvdownwardly to an opening 45 formed in member 16 which supports Wheels 15. Opening 45 constitutes the inlet to a blower member 46 contained within a housing 47 and directly driven by an electric motor 48. The blower draws ambient air in through an inlet opening 49 which may be positioned in the front wall 32 of cabinet 2. This air then passes to the back of the dryer and after passing through inlet 27 it passes over the heaters 25 so as to be heated and then through the drum, entering through openings 24. The air passing through the drum causes moisture contained in fabrics within the drum to be evaporated and entrains lint from the fabrics. The vitiated air then leaves the basket through opening 38 and passes down through openings 39 and 40 and through filter 42 which removes the lint from the stream of vitiated air. Then the air passes through duct 41 to blower 46' and is thereafter directed out of the cabinet 2 through a suitable duct (not shown).

In addition to driving blower 46, motor 48 constitutes the means for effecting rotation of drum 8. In order to effect this, motor 48 is provided with a shaft 50 having a small pulley 51 formed at the end thereof. A belt 52 extends around pulley 51 and also entirely around the cylindrical wall section 9 of drum -8. The relative circumferences of pulley 51 and wall section 9 cause the drum to be driven by the motor at a speed suitable to effect tumbling of clothes therein. In order to effect proper tensioning of belt 52 there may be provided a suitable idler assembly 53 secured on the same support,

54 which secures one end of the motor. Thus, the air is pulled through the drum; at the same time the fabrics in the drum are tumbled, and when the air is heated by heating elements 25 the heated air passing through the drum causes vaporization of the moisture in the clothes and picks up lint from the clothes. The lint is trapped in filter 42 and the vapor is carried off with the air as it passes out of the machine,

It can be seen that, since filter 42 substantially completely fills opening 40, as a layer of lint builds up on filtering member 44 the passage of air through filter 42 and thus duct 41 may be impaired. With previously employed filters, the user tended to let an excessive amount of lint build up in the filter. before cleaning because many of the prior art filters, such as mesh bags, were diflicult to clean under all circumstances and even filters which were improvement over the mesh bag type filter were diflicult to clean when only a relatively small amount of lint was in the filter.

My new and improved filter, one embodiment of which is shown in more detail in FIGURE 2, eliminates this problem by making it easy for the user to clean the filter even when there is a light load of lint in the filter. Filter 42 includes rigid frame 43 which fits on the top of member 33 and outer wall 32 of machine 2 to support the filter in opening 40. A filtering member 44 is attached to the frame43 and completely envelopes the central opening 55 defined by the frame. In the embodiment shown the filtering member includes a pair of spaced planar sidewalls 56 and 57 which extend from opposite sides of frame 43 and are provided with curved lower edges that are connected by means of ,a.

curved end wall 58, the end wall also being attached to the ends of frame 43.

As the air flows through filter 42 it enters the opening 55 and then flow-s through a plurality of small, closely spaced openings in the filtering member which strain the lint from the air. In the embodiment shown, the openings are provided by constructing filtering member 44 from a metal screen material. However, other structures may be utilized, for instance, the filtering member 44 could be formed from a sheet of perforated plastic material or it could be formedbytightly stretching a piece of cloth across the opening 55.

As the lint builds up on the filtering member various particles of lint become entangled in the openings in the filtering member and the various lint particles also become entangled with each other so as to form a mat of lint. If the mat is allowed to build up to a sufficient thickness the user may usual-1y grasp the mat at one edge and remove it from the filter, the. particles being sufficiently intertwined so that the lint comes out as a unitary body. However, when the covering of lint on the filter is still thin enough that it does not substantially interfere with the passage of air through the filter, the user has difiiculty in grasping the lint and itvtends to stick to the filtering member.

I have found that, by providing a narrow elongated imperforate rib 59 which extends across the bottom wall 58, the difliculty of removing a thin covering of lint is eliminated. The imperforate rib per-forms two functions;

first, it provides an area in which the lint particles are not intertwined in openings in the filtering member and, secondly, it provides a surface against which the user may. conveniently apply a sliding force. With my newand improved filter, all that the user is required to do is place her finger against the lint spanning the rib 59 at one end of the filter and then move her finger along the rib. With this action, even a light covering of lint will be quickly and easily removed from the filter as a unitary body.

As shown in FIGURE 2, rib 59 may take the form of a separate rod-like member which is secured withinframe 43 at each of its ends and lies in juxtaposition to end wall 58 along the entire length of the end wall. The features of having the rib raised from the surface of the filtering member and having the rib extend entirely across the filtering member provide the best result and are therefore incorporated in the preferred embodiment of my filter, as shown in FIGURE 2. However, neither of these features is absolutely necessary to the proper performance forate rib may be formed in the plane of the filtering member. In this regard, an imperforate rib of this type could easily be provided in a perforated plastic filtering member by merely excluding the perforations along a relatively narrow strip across the filtering member.

Additionally, ribs may be provided which extend inwardly from one or more of the edges of the filtering member across only a part of the surface of the filtering member. Such ribs enable the filter to be easily cleaned because, once a portion of the lint covering has been separated from the filtering member the entire body of lint tends easily to separate from the filter. With a rib which extends only partially across the filtering member the user is required to lift the lint from the filtering member in the form of a thin sheet. If the user jerks on the lint too vigorously it will separate and part ofthe lint will be retained on the filter. With a rib which extends completely across the filtering member the user merely runs her finger across the rib and causes the lint to be compressed into a compact body before she lifts it from the filter. Thus it will be seen that while a relatively short rib provides substantially easier cleaning, a rib extending completely across the filtering member is to be preferred.

While I have shown and described particular embodiments of my invention, I do not desire the invention to be limited to the particular constructions disclosed and I intend in the appended claims to cover all such modifications which fall Within the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. For use in a fabric drying machine including a chamber to receive fabrics to be dried, means for providing heat to the chamber to evaporate moisture from the fabrics, tumbling means to tumble fabrics in the chamber, and exhaust means including a duct for directing vitiated air from the chamber, a filter for removing lint from the vitiated air, said filter including a rigid frame for mounting in the duct and defining an inlet to said filter, a filtering member attached to said frame and having planar side walls and a curved end wall, said walls having a plurality of small, closely spaced openings for straining lint from the vitiated air, said trap further including a narrow, elongated imperforate rib extending in juxtaposition to said end wall to facilitate removal of accumulated lint from said filter,

2. A lint filter as set forth in claim 1 wherein said rib projects toward said filter inlet from said end wall.

3, A lint filter as set forth in claim 1 wherein said filtering member is formed from screen material and said rib is a rod-like member mounted in juxtaposition to the filter inlet side of said end Wall.

References Cited by the Examiner UNITED STATES PATENTS 799,575 9/ 1905 Overholt 379 X 1,779,458 10/1930 Annis 55-341 2,722,751 11/1955 Steward 34-82 2,814,357 11/1957 Bowman 55379 X 2,93 8,597 5/1960 Bolyai 55-379 X 3,167,409 1/1965 Brucken 34-82 X FOREIGN PATENTS 208,331 5/1957 Australia.

FREDERICK L. MATTESON, JR., Primary Examiner. DONLEY J. STOCKING, Examiner. C. R. REMKE, Assistant Examiner. 

1. FOR USE IN A FABRIC DRYING MACHINE INCLUDING A CHAMBER TO RECEIVE FABRICS TO BE DRIED, MEANS FOR PROVIDING HEAT TO THE CHAMBER TO EVAPORATE MOISTURE FROM THE FABRICS, TUMBLING MEANS TO TUMBLE FABRICS IN THE CHAMBER, AND EXHAUST MEANS INCLUDING A DUCT FOR DIRECTING VITIATED AIR FROM THE CHAMBER, A FILTER FOR REMOVING LINT FROM THE VITIATED AIR, SAID FILTER INCLUDING A RIGID FRAME FOR MOUNTING IN THE DUCT AND DEFINING AN INLET TO SAID FILTER, A FILTERING MEMBER ATTACHED TO SAID FRAME AND HAVING PLANAR SIDE WALLS AND A CURVED END WALL, SAID WALLS HAVING A PLURALITY OF SMALL, CLOSELY SPACED OPENINGS FOR STRAINING LINT FROM THE VITIATED AIR, SAID TRAP FURTHER INCLUDING A NARROW, ELONGATED IMPERFORATE RIB EXTENDING IN JUXTAPOSITION TO SAID END WALL TO FACILITATE REMOVAL OF ACCUMULATED LINT FROM SAID FILTER. 